diff --git a/VERSION b/VERSION
index 665274b2..ee02a8ca 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-Version 2.00.0 (2012-08-24 10:04:14) dev
+Version 2.00.0 (2012-08-24 10:13:35) dev
diff --git a/gluon/tools.py b/gluon/tools.py
index 4752f1c8..56a0c4a1 100644
--- a/gluon/tools.py
+++ b/gluon/tools.py
@@ -1412,7 +1412,8 @@ class Auth(object):
                 settings.table_user_name,[])+signature_list
             if username or settings.cas_provider:          
                 is_unique_username = \
-                    [IS_MATCH('[\w\.\-]+'), IS_NOT_IN_DB(db, table.username)]
+                    [IS_MATCH('[\w\.\-]+'), 
+                     IS_NOT_IN_DB(db,'%s.username' % settings.table_user_name)]
                 if not settings.username_case_sensitive:
                     is_unique_username.insert(1,IS_LOWER())
                 table = db.define_table(